As soon as we begin making room for prayer, all sorts of things begin to crowd in: memories, emotions, plans for future projects. And if we do manage to start praying, it does not seem long before our attention wanes and the process begins all over again.
Sometimes my prayer is a time of great inner stillness, and my spirit is possessed by what feels like God's nearness. That is good prayer. At other times I am tired and disgruntled; my efforts at prayer simply expose me to my own weakness, and I cry out to God from a very great distance. That is also good prayer.
Prayer may be rejoicing in the Spirit or writhing in anguish. It is good if it is real, and no good if it is delusion or play-acting.